miiiguel wrote:
I need some help. I have 99% of the items. By checking the inventory I can see I miss just an armour upgrade, though I have no more question marks on my map. Any idea, where it might be?

And, man... golden guns are so cool!

Yep. Couple of items are in save rooms so dont get a question mark on the map. Probably this one in the 'purple' zone: